Roll core, battery cell and battery

Abstract

The utility model provides a roll core, a battery cell and a battery, and relates to the technical field of batteries. The roll core comprises a roll core main body and a first tab, the roll core main body comprises a first pole piece, a diaphragm and a second pole piece, and the roll core main body is provided with a first end part along the axial direction of the roll core; the first tab is arranged at the first end part and is connected to the first pole piece; the multiple layers of first tabs are stacked at the first end part to form a first tab region, the first tab region extends along the circumferential direction of the roll core main body, and the outer diameter of the first tab region is smaller than that of the roll core main body; a plurality of first inner tab-free regions and a plurality of first outer tab-free regions are respectively arranged on the inner peripheral side, namely the outer peripheral side, of the first tab region. In the application, the plurality of first inner tab-free areas and the plurality of first outer tab-free areas are respectively arranged on the inner peripheral side and the outer peripheral side of the first tab area, so that the electrolyte can directly flow into the roll core through the tab-free area of the first end part, the path of the electrolyte to infiltrate the roll core can be shortened, and the infiltration efficiency of the roll core can be improved.

Description

Technical Field

[0001] This application relates to the technical field of batteries, and particularly relates to a wound core, an electrode core, and a battery. Background Art

[0002] In the related art, a battery includes a housing and a wound core disposed within the housing. The wound core includes a positive electrode sheet, a negative electrode sheet, and a separator that are sequentially stacked and wound. Among them, the electrode sheet includes a coating area and a blank foil area located at the periphery of the coating area. The coating area is used for coating active material, and the blank foil area serves as an electrode tab.

[0003] In order to control the height of the electrode tab inside the electrode core, it is necessary to flatten the electrode tab, that is, bend the electrode tab towards the end face of the wound core so that adjacent electrode tabs are stacked along the axial direction of the wound core to form an electrode tab area. However, the flattened electrode tab will block the end of the wound core, resulting in the electrolyte mainly flowing down through the middle hole of the wound core to the bottom of the inner cavity of the electrode core, and then adsorbing the electrolyte through the electrode sheet to adsorb the electrolyte to the top of the wound core to complete the infiltration of the wound core. In this way, the path of the electrolyte infiltrating the wound core is relatively long, resulting in poor infiltration efficiency of the wound core. Summary of the Utility Model

[0004] Embodiments of this application provide a wound core, an electrode core, and a battery, which can improve the infiltration efficiency of the wound core.

[0005] In a first aspect, an embodiment of this application provides a wound core, which includes a wound core body and a first electrode tab; the wound core body includes a first electrode sheet, a separator, and a second electrode sheet that are wound and arranged, the separator is located between the first electrode sheet and the second electrode sheet, the polarities of the first electrode sheet and the second electrode sheet are opposite, and along the axial direction of the wound core, the wound core body has a first end; the first electrode tab is disposed at the first end and is connected to the first electrode sheet; among them, multiple layers of first electrode tabs are stacked at the first end to form a first electrode tab area, the first electrode tab area extends along the circumferential direction of the wound core body, and the outer diameter of the first electrode tab area is smaller than the outer diameter of the wound core body; a plurality of first inner non-electrode tab areas are arranged on the inner circumferential side of the first electrode tab area, and a plurality of first outer non-electrode tab areas are arranged on the outer circumferential side of the first electrode tab area.

[0006] In an embodiment, taking the axial direction of the wound core as the projection direction, the projection of the first inner non-electrode tab area is a fan-shaped ring, and the small end of the fan-shaped ring faces the axis of the wound core.

[0007] In an embodiment, along the radial direction of the wound core, the first inner non-electrode tab area has a maximum dimension d1, and the outer diameter of the wound core body is A, satisfying: 0.1A ≤ d1 ≤ 0.3A.

[0008] In an embodiment, the central angle of the first inner non-electrode tab area is α1, satisfying: 10° ≤ α1 ≤ 45°.

[0009] In one embodiment, with the axial direction of the core as the projection direction, the projection of the first outer non-polar tab area is a fan-shaped ring, and the small end of the fan-shaped ring faces the axis of the core.

[0010] In one embodiment, along the radial direction of the core, the first inner non-polar tab area has a maximum dimension d2, and the outer diameter of the core body is A, satisfying: 0.1A ≤ d2 ≤ 0.3A.

[0011] In one embodiment, the central angle of the first outer non-polar tab area is α2, satisfying: 10° ≤ α2 ≤ 45°.

[0012] In one embodiment, the outer diameter of the first tab area is B, and the outer diameter of the core body is A, satisfying: 0.8A ≤ B < A.

[0013] In one embodiment, the inner diameter of the first tab area is C, and the outer diameter of the core body is A, satisfying: 0.02A ≤ C ≤ 0.25A.

[0014] In one embodiment, along the circumferential direction of the core body, a plurality of first inner non-polar tab areas and a plurality of first outer non-polar tab areas are arranged alternately in sequence.

[0015] In one embodiment, a plurality of first inner non-polar tab areas correspond to a plurality of first outer non-polar tab areas one by one. Along the circumferential direction of the core body, each first outer non-polar tab area has a deflection angle δ1 relative to the corresponding first inner non-polar tab area. The central angle of the first inner non-polar tab area is α1, the central angle of the first outer non-polar tab area is α2, and the number of the first inner non-polar tab areas is n, satisfying: α1 ≤ δ1 ≤ 360° / n - α2.

[0016] In one embodiment, the core further includes a second tab. The core has a second end opposite to the first end; the second tab is disposed at the second end and connected to the second tab; wherein, multiple layers of second tabs are stacked at the second end to form a second tab area. The second tab area extends along the circumferential direction of the core body. A plurality of second inner non-polar tab areas are disposed on the inner circumferential side of the second tab area, and a plurality of second outer non-polar tab areas are disposed on the outer circumferential side of the second tab area; a plurality of second inner non-polar tab areas correspond to a plurality of first inner non-polar tabs one by one. Along the circumferential direction of the core body, each second inner non-polar tab area has a deflection angle β1 relative to the corresponding first inner non-polar tab area, satisfying: 5° ≤ β1 ≤ 45°; and / or, a plurality of second outer non-polar tab areas correspond to a plurality of first outer non-polar tabs one by one. Along the circumferential direction of the core body, each second outer non-polar tab area has a deflection angle β2 relative to the corresponding first outer non-polar tab area, satisfying: 5° ≤ β2 ≤ 45°.

[0017] In a second aspect, an embodiment of the present application provides an electric core, which includes a housing, a cover plate, and the aforementioned core; the cover plate and the housing are covered to define a receiving cavity; the core is disposed in the receiving cavity.

[0018] In a third aspect, an embodiment of the present application provides a battery, which includes the aforementioned battery cell.

[0019] Advantageous effects of the embodiments of the present application:

[0020] In the embodiments of the present application, by respectively arranging a plurality of first inner non-tab areas and a plurality of first outer non-tab areas on the inner peripheral side and the outer peripheral side of the first tab area, the electrolyte can directly flow into the inside of the wound core through the first inner non-tab area and the first outer non-tab area, thereby shortening the path of the electrolyte to infiltrate the wound core, and further improving the infiltration efficiency of the wound core. Description of the Drawings

[0021] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following will briefly introduce the drawings required for the description of the embodiments. Obviously, the drawings in the following description are only some embodiments of the present application. For those skilled in the art, without creative efforts, other drawings can be obtained based on these drawings.

[0022] Figure 1 is a schematic structural diagram of a wound core provided by an embodiment of the present application;

[0023] Figure 2 is a schematic structural diagram of a first end portion provided by an embodiment of the present application;

[0024] Figure 3 is a schematic diagram of the deflection of a first outer non-tab area relative to the corresponding first inner non-tab area provided by an embodiment of the present application;

[0025] Figure 4 is a schematic diagram of the deflection of another first outer non-tab area relative to the corresponding first inner non-tab area provided by an embodiment of the present application;

[0026] Figure 5 is a schematic structural diagram of a second end portion provided by an embodiment of the present application;

[0027] Figure 6 is a schematic diagram of the deflection of a second inner non-tab area relative to the corresponding first inner non-tab area provided by an embodiment of the present application;

[0028] Figure 7 is a schematic structural diagram of a battery cell provided by an embodiment of the present application;

[0029] Figure 8 is a schematic structural diagram of a battery provided by an embodiment of the present application.

[0030] Description of the Reference Numerals:

[0031] 001 - Wound core;

[0032] 011 - Core body; 111 - First end; 1111 - First inner non - polar tab area; 1112 - First outer non - polar tab area; 112 - Second end; 1121 - Second inner non - polar tab area; 1122 - Second outer non - polar tab area; 113 - Intermediate hole;

[0033] 012 - First polar tab area; 121 - First polar tab;

[0034] 013 - Second polar tab area; 131 - Second polar tab;

[0035] 002 - Battery cell; 021 - Housing; 022 - Cover plate;

[0036] 003 - Battery; 031 - Box body. Detailed implementation mode

[0037] Next, the technical solutions in the embodiments of the present application will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without making creative efforts belong to the scope of protection of the present application.

[0038] In the description of the present application, it should be noted that unless otherwise clearly defined and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection, an electrical connection, or can communicate with each other; it can be directly connected, or indirectly connected through an intermediate medium, and can be the internal communication of two components or the interaction relationship between two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood according to specific circumstances.

[0039] The term "including", "comprising" or any other variant thereof is intended to cover non - exclusive inclusion, so that a process, method, article or device including a series of elements not only includes those elements, but also includes other elements not explicitly listed, or also includes elements inherent to such a process, method, article or device. Without further limitation, the element defined by the statement "including one..." does not exclude the existence of another identical element in the process, method, article or device including the said element.

[0040] For the convenience of understanding the solution of the present application, the spline curves and arrows used for the reference numerals in the accompanying drawings are described here: For the components indicated by the spline curves without arrows, they are solid components, that is, components with a solid structure; for the components indicated by the spline curves with arrows, they are virtual components, that is, components without a solid structure.

[0041] Please refer to Figure 1 and Figure 2 , Figure 1 which is a schematic structural view of the core 001 provided by an embodiment of the present application, Figure 2 and which is a schematic structural view of the first end portion 111 provided by an embodiment of the present application. An embodiment of the present application provides a core 001, which includes a core body 011 and a first tab 121; the core body 011 includes a first electrode tab, a separator, and a second electrode tab that are wound, the separator is located between the first electrode tab and the second electrode tab, the polarities of the first electrode tab and the second electrode tab are opposite, along the axial direction of the core 001, the core body 011 has a first end portion 111; the first tab 121 is disposed at the first end portion 111 and is connected to the first electrode tab; wherein, multiple layers of the first tabs 121 are stacked at the first end portion 111 to form a first tab region 012, the first tab region 012 extends along the circumferential direction of the core body 011, and the outer diameter of the first tab region 012 is smaller than the outer diameter of the core body 011; a plurality of first inner tabless regions 1111 are disposed on the inner circumferential side of the first tab region 012, and a plurality of first outer tabless regions 1112 are disposed on the outer circumferential side of the first tab region 012.

[0042] Wherein, the first tab region 012 may extend along the circumferential direction of the core body 011 to form an annular shape, or may extend along the circumferential direction of the core body 011 to form a sector-annular shape, and the sector-annular shape may be one or multiple. When there are multiple ones, the multiple sector-annular shapes are arranged at intervals along the circumferential direction of the core body 011. Wherein, the sector-annular shape means that the first tab region 012 extends along the circumferential direction of the core body 011 and the formed central angle is less than 360°.

[0043] It can be understood that the inner diameter and the outer diameter are the diameters of the relevant parts. The tabless region is the region where no tab is provided on the end face of the core 001. Before being bent, the tab is parallel to the axial direction of the core 001, and after being bent, the tabs are stacked in sequence along the axial direction of the core 001 to form a tab region.

[0044] Specifically, the first electrode tab includes a coating region coated with an active material and an uncoated region not coated with an active material. The first tab 121 can be integrally provided as at least part of the uncoated region. In other embodiments, the first tab 121 can be separately welded to the first electrode tab.

[0045] In addition, the first tab 121 can be a positive tab or a negative tab.

[0046] In this embodiment, by respectively arranging a plurality of first inner non-tab areas 1111 and a plurality of first outer non-tab areas 1112 on the inner peripheral side and the outer peripheral side of the first tab area 012, on the one hand, the electrolyte can directly flow into the inside of the core 001 through the first inner non-tab areas 1111 and the first outer non-tab areas 1112, so as to shorten the path of the electrolyte to infiltrate the core 001, and further improve the infiltration efficiency of the core 001; on the other hand, it can make the core 001 have a plurality of liquid inlet positions on the first end portion 111, and the plurality of liquid inlet positions respectively infiltrate inward along the outer periphery of the core 001 and infiltrate inward along the inner periphery of the core 001, which can improve the uniformity of the infiltration of the core 001, and thus can further improve the infiltration efficiency of the core 001.

[0047] In addition, by setting the outer diameter of the first tab area 012 to be smaller than the outer diameter of the core body 011, the outer periphery of the first tab area 012 can be spaced from the outer periphery of the core body 011, so as to avoid the first tab 121 exceeding the outer periphery of the core body 011 after the first tab 121 is flattened, and further control the radial dimension of the core 001 to facilitate the core 001 to enter the shell.

[0048] Please refer to Figure 2 , in one embodiment, with the axial direction of the core 001 as the projection direction, the projection of the first inner non-tab area 1111 is a fan-shaped ring. The small end of the fan-shaped ring faces the axis of the core 001.

[0049] It can be understood that with the plane perpendicular to the axis of the core 001 as the projection plane, the projection of the first inner non-tab area 1111 in the projection plane is a fan-shaped ring.

[0050] Among them, the center of the fan-shaped ring coincides with the center of the core 001.

[0051] In this embodiment, through the above settings, the dimension of the first inner non-tab area 1111 in the circumferential direction of the core 001 can be positively correlated with the circumferential dimension of the first tab area 012, so that on the one hand, the area of the first inner non-tab area 1111 can be increased to facilitate improving the infiltration efficiency, and on the other hand, the influence of the first inner non-tab area 1111 on the circumferential dimension of the first tab area 012 can be reduced to facilitate the operability and reliability of the welding of the first tab area 012 and the current collector plate.

[0052] Please refer to Figure 2 , in one embodiment, along the radial direction of the core 001, the first inner non-tab area 1111 has a maximum dimension d1, and the outer diameter of the core body is A, satisfying: 0.1A ≤ d1 ≤ 0.3A.

[0053] It can be understood that d1 includes but is not limited to: 0.1A, 0.12A, 0.133A, 0.15A, 0.16A, 0.18A, 0.2A, 0.22A, 0.25A, 0.3A.

[0054] Exemplarily,

[0055] When A is 44.6 mm, d1 is 4.46 mm to 13.38 mm;

[0056] When A is 45 mm, d1 is 4.5 mm to 13.5 mm;

[0057] When A is 45.2 mm, d1 is 4.52 mm to 13.56 mm.

[0058] In this embodiment, by limiting the maximum size of the first inner non-pole-ear region 1111, on the one hand, it can be avoided that the size is too large, resulting in a smaller size of the first pole-ear region 012 in the radial direction where the first inner non-pole-ear region 1111 is located. Thus, the first pole-ear region 012 can have a larger area in this radial direction, and further, the ease of operation and reliability of welding the first pole-ear region 012 to the current collector plate can be improved.

[0059] Please refer to Figure 2 , in one embodiment, the central angle of the first inner non-pole-ear region 1111 is α1, satisfying: 10° ≤ α1 ≤ 45°.

[0060] It can be understood that α1 includes but is not limited to 10°, 12°, 14.5°, 16°, 17°, 18°, 19°, 20°, 22°, 26°, 29°, 30°, 36°, 38°, 39°, 40°, 42.5°, 44°, 45°.

[0061] Further, 20° ≤ α1 ≤ 35°.

[0062] In this embodiment, through the above limitation, on the one hand, it can be avoided that the size of the first inner non-pole-ear region 1111 in the circumferential direction of the core 001 is too small, which is not conducive to the flow of the electrolyte. On the other hand, it can be avoided that the size of the first inner non-pole-ear region 1111 in the circumferential direction of the core 001 is too large, resulting in a too small area of the first pole-ear region 012 at the circumference where the first inner non-pole-ear region 1111 is located. Thus, it can be ensured that the first pole-ear region 012 at the circumference where the first inner non-pole-ear region 1111 is located has a larger area, and further, the ease of operation and reliability of welding the first pole-ear region 012 located at this circumference to the current collector plate can be ensured.

[0063] In one embodiment, with the axial direction of the core 001 as the projection direction, the projection of the first outer non-pole-ear region 1112 is a fan-shaped ring, and the small end of the fan-shaped ring faces the axis of the core 001.

[0064] It can be understood that with a plane perpendicular to the axis of the core 001 as the projection plane, the projection of the first outer non-pole-ear region 1112 in the projection plane is a fan-shaped ring.

[0065] In this embodiment, through the above settings, the size of the first outer non-tab area 1112 in the circumferential direction of the core 001 can be made positively correlated with the circumferential size of the first tab area 012. Thus, on one hand, the area of the second outer non-tab area 1122 can be increased to facilitate the improvement of the infiltration efficiency, and on the other hand, the influence of the first outer non-tab area 1112 on the circumferential size of the first tab area 012 can be reduced to facilitate the operability and reliability of the welding of the first tab area 012 to the current collector plate.

[0066] Please refer to Figure 2 , in one embodiment, along the radial direction of the core 001, the first outer non-tab area 1112 has a maximum size d2, and the outer diameter of the core body 011 is A, satisfying: 0.1A ≤ d2 ≤ 0.3A.

[0067] It can be understood that d2 includes but is not limited to: 0.1A, 0.12A, 0.133A, 0.15A, 0.16A, 0.18A, 0.2A, 0.22A, 0.25A, 0.3A.

[0068] Exemplarily,

[0069] When A is 44.6 mm, d2 is 4.46 mm to 13.38 mm;

[0070] When A is 45 mm, d2 is 4.5 mm to 13.5 mm;

[0071] When A is 45.2 mm, d2 is 4.52 mm to 13.56 mm.

[0072] In this embodiment, by limiting the maximum size of the first outer non-tab area 1112, on one hand, it can be avoided that the size is too large, resulting in a smaller size of the first tab area 012 in the radial direction where the first outer non-tab area 1112 is located. Thus, the first tab area 012 can have a larger area in this radial direction, and further, the operability and reliability of the welding of the first tab area 012 to the current collector plate can be improved.

[0073] Please refer to Figure 2 , in one embodiment, the central angle of the first outer non-tab area 1112 is α2, satisfying: 10° ≤ α2 ≤ 45°.

[0074] It can be understood that α2 includes but is not limited to 10°, 12°, 14.5°, 16°, 17°, 18°, 19°, 20°, 22°, 26°, 29°, 30°, 36°, 38°, 39°, 40°, 42.5°, 44°, 45°.

[0075] Furthermore, 20° ≤ α2 ≤ 35°.

[0076] In this embodiment, through the above limitations, on the one hand, it can be avoided that the size of the first outer non-pole-ear region 1112 in the circumferential direction of the core 001 is too small, which is not conducive to the flow of the electrolyte. On the other hand, it can be avoided that the size of the first outer non-pole-ear region 1112 in the circumferential direction of the core 001 is too large, resulting in too small an area of the first pole-ear region 012 at the circumference where the first inner and outer pole-ear regions are located. Thus, it can be ensured that the first pole-ear region 012 at the circumference where the first outer non-pole-ear region 1112 is located has a larger area, and further, the operability and reliability of welding the first pole-ear region 012 located at this circumference to the current collector plate can be ensured.

[0077] Please refer to Figure 2 , in one embodiment, the outer diameter of the first pole-ear region 012 is B, and the outer diameter of the core body 011 is A, satisfying: 0.8A ≤ B < A.

[0078] It can be understood that B includes but is not limited to: 0.8A, 0.81A, 0.81.5A, 0.82A, 0.83A, 0.84A, 0.85A, 0.86A, 0.88A, 0.9A, 0.92A, 0.95A, 0.99A.

[0079] Exemplarily,

[0080] When A is 44.6 mm, 35.68 mm ≤ B < 44.6 mm;

[0081] When A is 45 mm, 36 mm ≤ B < 45 mm;

[0082] When A is 45.2 mm, 36.16 mm ≤ B < 45.2 mm.

[0083] Further, 0.8A ≤ B ≤ 0.95A.

[0084] In this embodiment, through the above limitations, on the one hand, a gap can be formed between the outer periphery of the first pole-ear region 012 and the outer periphery of the core body 011. Thus, the core 001 can be infiltrated through this gap to improve the infiltration efficiency, and the size of this end of the core 001 can be controlled to facilitate the insertion of the core 001 into the shell. On the other hand, it can be avoided that the outer diameter of the first pole-ear region 012 is too small, resulting in a smaller area of the first pole-ear 121. Thus, the area of the first pole-ear 121 can be ensured, so that the current collection capacity of the first pole piece meets the requirements.

[0085] Please refer to Figure 2 , in one embodiment, the inner diameter of the first pole-ear region 012 is C, and the outer diameter of the core body 011 is A, satisfying: 0.02A ≤ C ≤ 0.25A.

[0086] It can be understood that C includes but is not limited to: 0.02A, 0.06A, 0.08A, 0.1A, 0.11A, 0.12A, 0.15A, 0.18A, 0.2A, 0.4A, 0.25A.

[0087] Exemplarily,

[0088] When A is 44.6 mm, 0.892 mm ≤ C ≤ 11.5 mm;

[0089] When A is 45 mm, 0.9 mm ≤ C ≤ 11.25 mm;

[0090] When A is 45.2 mm, 0.904 mm ≤ C ≤ 11.3 mm.

[0091] Further, 0.1A ≤ C ≤ 0.25A.

[0092] In this embodiment, through the above limitations, on the one hand, it is possible to avoid the first tab area 012 from blocking the middle hole 113 of the core 001, thereby ensuring the smooth flow of the electrolyte; on the other hand, it is possible to avoid the inner diameter of the first tab area 012 from being too large, resulting in a small area of the first tab 121, thereby ensuring the area of the first tab 121 so that the current collecting capacity of the first electrode sheet meets the requirements.

[0093] Please refer to Figure 2 , in one embodiment, along the circumferential direction of the core body 011, a plurality of first inner tabless areas 1111 and a plurality of first outer tabless areas 1112 are alternately arranged in sequence.

[0094] In this embodiment, by alternately arranging a plurality of first inner tabless areas 1111 and a plurality of first outer tabless areas 1112 in sequence, at least part of the first inner tabless area 1111 and the first outer tabless area 1112 can be made non-opposite, thereby ensuring a relatively large area of the first tab area 012 between the first inner tabless area 1111 and the first outer tabless area 1112, and further ensuring the ease of operation and reliability of welding the first tab area 012 located between the first inner tabless area 1111 and the first outer tabless area 1112 to the current collecting plate.

[0095] Please refer to Figure 2 , in one embodiment, a plurality of first inner tabless areas 1111 correspond to a plurality of first outer tabless areas 1112 one by one. Along the circumferential direction of the core body 011, each first outer tabless area 1112 has a deflection angle δ1 relative to the corresponding first inner tabless area 1111. The central angle of the first inner tabless area 1111 is α1, the central angle of the first outer tabless area 1112 is α2, and the number of the first inner tabless areas 1111 is n, satisfying: α1 ≤ δ1 ≤ 360° / n - α2.

[0096] Exemplarily, when n = 2, α1 ≤ δ1 ≤ 180° - α2, as Figure 3 shown, Figure 3 is a schematic diagram of the deflection of the first outer tabless area 1112 relative to the corresponding first inner tabless area 1111 provided by an embodiment of the present application. The dashed line in the figure is the maximum position where the first outer tabless area 1112 shown by the thick line can deflect relative to the corresponding first inner tabless area 1111.

[0097] When n = 3, α1 ≤ δ1 ≤ 120° - α2, as Figure 4 shown, Figure 4 is another schematic diagram of the deflection of the first outer tabless area 1112 relative to the corresponding first inner tabless area 1111 provided by an embodiment of the present application. The dashed line in the figure is the maximum position where the first outer tabless area 1112 shown by the thick line can deflect relative to the corresponding first inner tabless area 1111.

[0098] Specifically, 2 ≤ n ≤ 6.

[0099] In this embodiment, through the above limitations, the first outer tabless area 1112 and the first inner tabless area 1111 can be completely staggered, so as to increase the area of the first tab area 012 between the first inner tabless area 1111 and the first outer tabless area 1112, and further improve the operability and reliability of welding the first tab area 012 located between the first inner tabless area 1111 and the first outer tabless area 1112 to the current collector plate.

[0100] Please refer to Figure 5 , Figure 5 is a schematic diagram of the structure of the second end portion 112 provided by an embodiment of the present application. In one embodiment, the winding core 001 further includes a second tab 131. The winding core 001 has a second end portion 112 opposite to the first end portion 111; the second tab 131 is disposed on the second end portion 112 and connected to the second pole piece; wherein, multiple layers of the second tabs 131 are stacked on the second end portion 112 to form a second tab area 013. The second tab area 013 extends along the circumferential direction of the winding core body 011. A plurality of second inner tabless areas 1121 are provided on the inner circumferential side of the second tab area 013, and a plurality of second outer tabless areas 1122 are provided on the outer circumferential side of the second tab area 013.

[0101] Among them, the second tab area 013 can extend along the circumferential direction of the winding core body 011 to form a ring, or the second tab area 013 extends along the circumferential direction of the winding core body 011 to form a sector ring. The sector ring can be one or multiple. When there are multiple sector rings, the multiple sector rings are arranged at intervals along the circumferential direction of the winding core body 011. The sector ring means that the second tab area 013 extends along the circumferential direction of the winding core body 011, and the shape formed by the extension with a central angle less than 360°.

[0102] Specifically, the second pole piece includes a coated area coated with active material and an uncoated area not coated with active material. The second tab 131 can be integrally provided as at least a partial area of the uncoated area. In other embodiments, the second tab 131 can be separately welded to the second pole piece.

[0103] In addition, among the first tab 121 and the second tab 131, one is a positive tab and the other is a negative tab. Generally, the tab close to the top cover of the battery cell is set as the positive tab.

[0104] In this embodiment, through the above settings, the second end portion 112 can have a plurality of channels for the electrolyte to infiltrate into the battery cell, thereby improving the infiltration efficiency of the wound core 001; on the other hand, the wound core 001 can have a plurality of liquid inlet sites on the second end portion 112, and the multiple liquid inlet distributions respectively infiltrate inward along the outer circumference of the wound core 001 and inward along the inner circumference of the wound core 001, which can improve the uniformity of the infiltration of the wound core 001, thereby further improving the infiltration efficiency of the wound core 001.

[0105] Among them, the structures and layouts of the second tab area 013, the second inner tabless area 1121, and the second outer tabless area 1122 on the second end portion 112 are respectively the same as the structures and layouts of the first tab area 012, the second inner tabless area 1121, and the first outer tabless area 1112 on the first end portion 111. Specifically as follows:

[0106] Along the circumferential direction of the wound core body 011, a plurality of second inner tabless areas 1121 and a plurality of second outer tabless areas 1122 are arranged alternately in sequence.

[0107] Further, taking the axial direction of the wound core 001 as the projection direction and the plane perpendicular to the axis of the wound core 001 as the projection plane, the projection of the second inner tabless area 1121 in the projection plane is a fan-shaped ring, the small end of the fan-shaped ring faces the axis of the wound core 001, and the projection of the second outer tabless area 1122 in the projection plane is a fan-shaped ring, the small end of the fan-shaped ring faces the axis of the wound core 001.

[0108] Specifically, the central angle of the second inner tabless area 1121 is α3, satisfying: 10° ≤ α3 ≤ 45°. Further, 20° ≤ α3 ≤ 35°.

[0109] The central angle of the second outer tabless area 1122 is α4, satisfying: 10° ≤ α4 ≤ 45°. Further, 20° ≤ α4 ≤ 35°.

[0110] Among them, multiple second inner tabless regions 1121 correspond to multiple second outer tabless regions 1122 one by one. Along the circumferential direction of the core body 011, the second outer tabless region 1122 has a deflection angle δ2 relative to the corresponding second inner tabless region 1121. The central angle of the first inner tabless region 1111 is α3, the central angle of the first outer tabless region 1112 is α4, and the number of the second inner tabless regions 1121 is n, satisfying: α3 ≤ δ2 ≤ 360° / n - α4.

[0111] Please refer to Figure 5 , in an embodiment, multiple second inner tabless regions 1121 correspond to multiple first inner tabless regions one by one. Along the axial direction of the core 001, multiple second inner tabless regions 1121 and multiple first inner tabless regions are at most partially opposite, and / or multiple second outer tabless regions 1122 correspond to multiple first outer tabless regions one by one, and multiple second outer tabless regions 1122 and multiple first outer tabless regions 1112 are at most partially opposite.

[0112] Further, please refer to Figure 6 , Figure 6 is a schematic diagram of the deflection of the second inner tabless region relative to the corresponding first inner tabless region provided by the embodiment of the present application. Multiple second inner tabless regions 1121 correspond to multiple first inner tabless regions one by one. Along the circumferential direction of the core body 011, each second inner tabless region 1121 has a deflection angle β1 relative to the corresponding first inner tabless region 1111, satisfying: 5° ≤ β1 ≤ 45°; and / or multiple second outer tabless regions 1122 correspond to multiple first outer tabless regions one by one. Along the circumferential direction of the core body 011, each second outer tabless region 1122 has a deflection angle β2 relative to the corresponding first outer tabless region 1112, satisfying: 5° ≤ β2 ≤ 45°.

[0113] Specifically, the second inner tabless region 1121 has a deflection angle β1 relative to the corresponding first inner tabless region 1111, or the second outer tabless region 1122 has a deflection angle β2 relative to the corresponding first outer tabless region 1112, or the second inner tabless region 1121 has a deflection angle β1 relative to the corresponding first inner tabless region 1111, and the second outer tabless region 1122 has a deflection angle β2 relative to the corresponding first outer tabless region 1112.

[0114] It can be understood that β1 and β2 include but are not limited to 5°, 8°, 10°, 12.5°, 15°, 18°, 19°, 20°, 21.2°, 24°, 25°, 27°, 29°, 35°, 38°, 40°, 42°, 45°.

[0115] In this embodiment, through the above settings, the tabless area of the second end portion 112 is deflected relative to the tabless area of the first end portion 111. On the one hand, the first end portion 111 and the second end portion 112 can respectively receive liquid from different radial positions of the core 001, thereby further improving the uniformity of the infiltration of the core 001 and then enhancing the infiltration efficiency of the core 001. On the other hand, the first inner tabless area 1111 and the second inner tabless area 1121 can be at least partially arranged opposite to the second tab area 013. Thus, when the electrode liquid flowing into the core 001 from the first inner tabless area 1111 and the second inner tabless area 1121 is discharged from the second end portion 112, the discharge of this part of the electrolyte is slowed down due to the obstruction of the second tab area 013, so that more electrolyte can be retained in the core 001, thereby enhancing the electrolyte infiltration efficiency.

[0116] In one embodiment, with the axial direction of the core 001 as the projection direction and the plane where the first end portion 111 is located as the projection plane, the area of the first tab area 012 in the projection plane is S1, and the area of the first end portion 111 is S, satisfying: 0.5 ≤ S1 / S < 1.

[0117] With the axial direction of the core 001 as the projection direction and the plane where the second end portion 112 is located as the projection plane, the area of the second tab area 013 in the projection plane is S2, and the area of the second end portion 112 is S, satisfying: 0.5 ≤ S2 / S < 1. Further, 0.5 ≤ S2 / S ≤ 0.8.

[0118] Exemplarily, the ratio of S1 to S and the ratio of S2 to S include but are not limited to: 0.5, 0.52, 0.55, 0.58, 0.6, 0.62, 0.63, 0.64, 0.66, 0.66, 0.68, 0.7, 0.72, 0.76, 0.78, 0.8, 0.85, 0.9, 0.95.

[0119] Further, 0.5 ≤ S1 / S ≤ 0.8, 0.5 ≤ S2 / S ≤ 0.8.

[0120] In this embodiment, through the above limitations, on the one hand, the first tab area 012 and the second tab area 013 can have sufficient areas to meet the current collection requirements of the core 001. On the other hand, it can be avoided that the areas of the first tab area 012 and the second tab area 013 are too large, resulting in too small an area of the tabless area on the same end face, so as to ensure the liquid inlet speed of the two end faces of the core 001 and facilitate improving the infiltration efficiency of the core 001.

[0121] Please refer to Figure 7 , Figure 7It is a schematic structural diagram of the battery cell 002 provided by an embodiment of the present application. Correspondingly, an embodiment of the present application provides a battery cell 002, which includes a housing 021, a cover plate 022, and the aforementioned wound core 001; the cover plate 022 is covered with the housing 021 to define a receiving cavity; the wound core 001 is disposed in the receiving cavity.

[0122] In this embodiment, by adopting the aforementioned wound core 001, on the one hand, the electrolyte can directly flow into the inside of the wound core 001 through the top of the wound core 001, thereby shortening the path of the electrolyte to infiltrate the wound core 001, and further improving the infiltration efficiency of the battery cell 002; on the other hand, the wound core 001 can have a plurality of liquid inlet parts at the first end 111, and the plurality of liquid inlet parts respectively infiltrate inward along the outer circumference and the inner circumference of the wound core 001, which can improve the uniformity of the infiltration of the wound core 001, and further improve the infiltration efficiency of the battery cell 002.

[0123] Please refer to Figure 8 , Figure 8 It is a schematic structural diagram of the battery 003 provided by an embodiment of the present application. An embodiment of the present application provides a battery 003, which includes the aforementioned battery cell 002.

[0124] It can be understood that the battery 003 may further include a box body or a bottom plate, the battery cell 002 is disposed in the box body, or the battery cell 002 is mounted on the bottom plate.

[0125] In this embodiment, by adopting the aforementioned battery cell 002, on the one hand, the electrolyte can directly flow into the inside of the wound core 001 through the top of the wound core 001, thereby shortening the path of the electrolyte to infiltrate the wound core 001, and further improving the manufacturing efficiency of the battery 003; on the other hand, the wound core 001 can have a plurality of liquid inlet parts at the first end 111, and the plurality of liquid inlet parts respectively infiltrate inward along the outer circumference and the inner circumference of the wound core 001, which can improve the uniformity of the infiltration of the wound core 001, and further improve the manufacturing efficiency of the battery 003.

[0126] The above has introduced the embodiments of the present application in detail. Specific examples are used in this article to elaborate on the principle and implementation manner of the present application. The description of the above embodiments is only used to help understand the method and its core idea of the present application; at the same time, for those skilled in the art, according to the idea of the present application, there will be changes in the specific implementation manner and application scope. In summary, the content of this specification should not be construed as a limitation to the present application.

Claims

1. A core, characterized in that, Comprising: A core body, including a first pole piece, a separator, and a second pole piece wound around, the separator being located between the first pole piece and the second pole piece, the polarities of the first pole piece and the second pole piece being opposite, along the axial direction of the core, the core body has a first end; A first pole tab, disposed at the first end and connected to the first pole piece; Wherein, multiple layers of the first pole tabs are stacked at the first end to form a first pole tab region, the first pole tab region extends along the circumferential direction of the core body, and the outer diameter of the first pole tab region is smaller than the outer diameter of the core body; A plurality of first inner non-pole-tab regions are provided on the inner circumferential side of the first pole tab region, and a plurality of first outer non-pole-tab regions are provided on the outer circumferential side of the first pole tab region.

2. The core according to claim 1, wherein Taking the axial direction of the core as the projection direction, the projection of the first inner non-pole-tab region is a fan-shaped ring, and the small end of the fan-shaped ring faces the axis of the core.

3. The core according to claim 2, characterized in that, Along the radial direction of the core, the first inner non-pole-tab region has a maximum dimension d1, and the outer diameter of the core body is A, satisfying: 0.1A ≤ d1 ≤ 0.3A.

4. The core according to claim 2, characterized in that, The central angle of the first inner non-pole-tab region is α1, satisfying: 10° ≤ α1 ≤ 45°.

5. The core roll according to any one of claims 1-4, characterized in that, Taking the axial direction of the core as the projection direction, the projection of the first outer non-pole-tab region is a fan-shaped ring, and the small end of the fan-shaped ring faces the axis of the core.

6. The core according to claim 5, characterized in that, Along the radial direction of the core, the first inner non-pole-tab region has a maximum dimension d2, and the outer diameter of the core body is A, satisfying: 0.1A ≤ d2 ≤ 0.3A.

7. The core according to claim 5, characterized in that, The central angle of the first outer non-pole-tab region is α2, satisfying: 10° ≤ α2 ≤ 45°.

8. The core according to any one of claims 1-4, characterized in that, The outer diameter of the first pole tab region is B, and the outer diameter of the core body is A, satisfying: 0.8A ≤ B < A.

9. The core according to any one of claims 1-4, characterized in that, The inner diameter of the first pole tab region is C, and the outer diameter of the core body is A, satisfying: 0.02A ≤ C ≤ 0.25A.

10. The core according to any one of claims 1-4, characterized in that, Along the circumferential direction of the core body, the plurality of first inner non-pole-tab regions and the plurality of first outer non-pole-tab regions are alternately arranged in sequence.

11. The core according to claim 10, characterized in that, The plurality of first inner non-pole-tab regions and the plurality of first outer non-pole-tab regions are in one-to-one correspondence. Along the circumferential direction of the core body, each first outer non-pole-tab region has a deflection angle δ1 relative to the corresponding first inner non-pole-tab region. The central angle of the first inner non-pole-tab region is α1, the central angle of the first outer non-pole-tab region is α2, and the number of the first inner non-pole-tab regions is n, satisfying: α1 ≤ δ1 ≤ 360° / n - α2.

12. The core according to any one of claims 1-4, characterized in that, The core further includes a second pole tab. The core has a second end opposite to the first end; the second pole tab is disposed at the second end and connected to the second pole piece; Wherein, multiple layers of the second pole tabs are stacked at the second end to form a second pole tab region, the second pole tab region extends along the circumferential direction of the core body, a plurality of second inner non-pole-tab regions are provided on the inner circumferential side of the second pole tab region, and a plurality of second outer non-pole-tab regions are provided on the outer circumferential side of the second pole tab region; A plurality of the second inner tabless regions correspond to a plurality of the first inner tabless regions one by one. Along the circumferential direction of the core body, each of the second inner tabless regions has a deflection angle β1 relative to the corresponding first inner tabless region, satisfying: 5° ≤ β1 ≤ 45°; And / or, a plurality of the second outer tabless regions correspond to a plurality of the first outer tabless regions one by one. Along the circumferential direction of the core body, each of the second outer tabless regions has a deflection angle β2 relative to the corresponding first outer tabless region, satisfying: 5° ≤ β2 ≤ 45°.

13. A battery cell, characterized in that, Comprising: A housing; A cover plate, which is covered with the housing to define an accommodation cavity; And, the core as described in any one of claims 1-12, which is disposed in the accommodation cavity.

14. A battery, characterized in that, Comprising the battery cell as described in claim 13.

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